BRAZILIAN biologists and medical men have made, and are making, valuable contributions to knowledge. The wide field which they cover is indicated, not only by their medical journals, but also by the policy of some of their biological periodicals, which publish articles on subjects which, in other countries, would be printed in medical literature. Thus the Revista Brazileira de Biologia (3, No. 4; 1943) contains papers on immunology, such as those on protection tests with Felix's antityphoid serum, on oxidation and reduction of complement and on the antibodies to the virus of equine encephalo-myelitis; and others on cryo-epilepsy, on Henry's melano-flocculation reaction and on Wolff's buffer-precipitation test in malaria, Chagas's disease and schistosomiasis. Another paper discusses the action of acetylcholine and of adrenalin on the coronary arteries of the Brazilian macacus monkey, Allouata fusous. The rest of this issue deals with more specifically biological subjects. Thus there are articles on two Lepidoptera, Automolis and Rhipha; and on the unity or duality of the males of the hymen opterous parasite, Telenomus fariai, in which the author concludes that the two classes of males are morphologically identical, produce the same progeny from the female and always have ten chromosomes, while the female has twenty. Their difference in size depends on the amount of food that is available. Other articles deal with a new trematode species, Catadiscus mirandai, from the large intestine of Hemipipa carvalhoi, with some spiders of Chile, with two new species of Stenolemus (Reduviidæ, Hemiptera) and with the hyoid and laryngeal apparatus of some Microchiroptera. Botanists will be interested in the article on the nomenclature of Capsicodendron Dinisii (syn. C. pimentiera, Canellaceæ). The social importance of scientific investigation is discussed by Dr. Oswaldo Cruz, of the famous Institute which bears his name.